ggm 8 hours ago

TRISO fuel so.. pebble bed? Is there a reluctance to market on this? The Chinese were all-in.

Great to see engineering deliver on time. I wonder if Rolls Royce will also have a smooth ride. It's a PWR.

  • chickenbig 8 hours ago

    Prismatic (or cylindrical) TRISO also makes sense. There are lots of potential problems using pebble beds (circulation, grinding), whereas doing regular refuelling cycles avoids them, in exchange for down-time to refuel.

  • pfdietz 6 hours ago

    TRISO increases fuel cycle costs. It's harder to make, harder to dispose of, and (IIRC) uses higher enrichment.

seanhunter 8 hours ago

Congrats to everyone involved. This is a pretty awesome milestone

  • mDyJzDPmBdG 7 hours ago

    To add a bit of context there were 11 companies participating in program and only 2 achieved critiality, and the deadline included in "DOE Reactor Pilot Program" was "July 4, 2026", and Aalo Atomics is the only one that might also make it in time.

    • netsharc 4 hours ago

      Sigh, everything is being done for political purposes, now Dear Leader Donny can proclaim on the quartermillenial celebrations that "we achieved a nuclear milestone!". And maybe add that this is possible because of his nuclear physics genius abilities.

      I wouldn't even be surprised if the achievements are like "Full-Self Driving", announced hastily with boasts and then slowly revealed to be full of Elon.

      • Gud 3 hours ago

        Honestly these political rants contribute very little, no offence.

        • bigbadfeline 2 hours ago

          > Honestly these political rants contribute very little, no offence.

          What do the other comments contribute? Do they solve inflation, wars, monopolization? Small-picture comments have small audience, like, how many people have access to nuclear materials and gear to make use of the information provided here? In other words "political rants" have their place and in many cases they are more valuable than the rest.

NoGravitas 2 hours ago

Other than "not light-water", what type of reactor is it?

  • philipkglass 33 minutes ago

    Graphite-moderated core, passively cooled with sodium filled heat pipes:

    https://antaresindustries.com/

    It also uses a Brayton cycle generator with nitrogen instead of steam.

    (See 03, 04, 06 in their schematic outline.)

coldtea 6 hours ago

That's just what we needed! Nuclear autotune.

  • cadamsdotcom 6 hours ago

    We need progress, not a decade per step.

    That distinction matters because nuclear.

    Let that sink in for a moment.

    • kibibu 4 hours ago

      (psst autotune is made by a company called Antares)

tech_ken 4 hours ago

From the article: > We said criticality in 2026, electricity production in 2027, and power to the warfighter in 2028.

Are there any other examples of land-based militaries using nuclear power? Seems kind of like since they can't talk about the energy transition or w/e this has to be a military thing instead.

  • actionfromafar 3 hours ago

    "Stalin is proud to support the rebirth of Soviet Russia’s nuclear industry and ensuring soviets have access to affordable, reliable and secure energy for generations to come". Always mention the fearless leader.

api 5 hours ago

Is anyone working in the US on a waste solution that isn’t a big hole with a straight out of cyberpunk sci-fi warning plaque?

The French reprocess and recycle fissile material but that’s kind of a gnarly industrial process. Still they do it and it works.

The long term solution is to create a second kind of reactor that has a higher burn fraction which means a more fuel efficient fast reactor. Those would be, ideally, the big base load plants if we did this rationally.

  • pfdietz 5 hours ago

    IMO, the long term solution will be to simply launch the waste into space. With low enough launch costs the extra mass needed to armor the waste against accidents becomes tolerable.

    • jampekka 4 hours ago

      Can't wait for one of those launch rockets to explode in the atmosphere!

      • hgoel 4 hours ago

        The requirements for a rocket to be allowed to fly nuclear material tend to be even more stringent than those for flying humans.

      • pfdietz 4 hours ago

        And the armored waste carriers to fall back to Earth and be recovered for relaunch.

    • api 4 hours ago

      Economically absurd, much more expensive than reprocessing or fast waste burning reactors.

      • pfdietz 4 hours ago

        I don't think that's the case, if launch costs are low enough. The options you describe there are quite expensive. Reprocessing costs somewhere in the neighborhood of $1000/kg. Even fast reactor have trouble disposing of the seven very long lived fission products. A fully reusable launcher might get costs down to $10/kg to LEO. Even if one had to wrap the waste in 10x its mass in launch armor this could be much cheaper than reprocessing.

        • dpark 3 hours ago

          Why would launch costs be low? $10/kg is fantasy land. UPS won’t ship a kilogram across the country for $10.

          And who wants spent nuclear fuel in low earth orbit? This is a far worse location for spent fuel than buried in a bunker. This is a worse location than Times Square.

          • pfdietz 3 hours ago

            Why wouldn't they be low? In the limit, if launch becomes operationally similar to air travel, costs will be a few times propellant cost. And propellant is very cheap. LOX is almost free (the second cheapest industrial liquid after water) and liquid methane isn't very expensive either.

            Low earth orbit would just be where it's transferred to something to carry it farther out, for example using solar-electric engines.

            For all this, remember it isn't done immediately, it's done in (say) 300 years when the short lived fission products are mostly gone.

            • dpark 2 hours ago

              I think the onus is on you to explain why costs would drop by >3 orders of magnitude (>4 accounting for the 10x launch armor). It’s something like $1500/lb on a fully loaded Falcon Heavy and all indications are that SpaceX isn’t making money at that price.

              Plus even if this were free, “shoot 180k tons of nuclear waste into space” seems like a terrible idea in general. It’s one of those ideas that make sense only until you think about the ramifications. What happens when inevitably one of the 3 thousand Falcon heavy rockets explodes and the armor fails and we spread nuclear waste over 3 states?

              • pfdietz 2 hours ago

                Falcon Heavy is more expensive per kg than F9, because it throws away more things. SpaceX flies it for certain military missions but you will note they launch their own stuff on F9.

                A full launch on F9 (with recovered S1) is estimated to cost $15M and can put up to 17,600 kg into LEO, or $850/kg.

                > (>4 accounting for the 10x launch armor).

                You're double counting there. 3x would be just fine even with 10x launch armor.

                > seems like a terrible idea in general

                And here's the problem: you started from an emotional reaction and are trying to rationalize that.

                • dpark 1 hour ago

                  > A full launch on F9 (with recovered S1) is estimated to cost $15M

                  Estimated by who? SpaceX charges 74 million for this. Nothing credible I can find indicates that SpaceX is running an amazing 80% profit margin on Falcon 9 launches.

                  > And here's the problem: you started from an emotional reaction and are trying to rationalize that.

                  No, your premise is “just launch the trash into space” and you’re hand waving away the complexity, costs, and danger.

          • api 2 hours ago

            $10/kg isn’t fantasy land if we have fusion rockets, but then we don’t need fission power anymore. :)

            • pfdietz 2 hours ago

              Fusion would be useless for launch to orbit. Even fission sucks for that. It's really hard to beat the cost and power density of chemical rockets.

          • fc417fc802 8 minutes ago

            > UPS won’t ship a kilogram across the country for $10.

            I can purchase produce grown on a different continent for less than that at the grocery store so something isn't right here.

    • hgoel 4 hours ago

      Probably not worthwhile. If you just leave it in orbit you're going to have to track it and worry about debris/micrometeoroid strikes. The ideal would be to stick it in some permanently shadowed crater on the Moon, it'd be a stable environment without wild temperature swings and much lower risk of somehow ending up where people are. But that's a long way to go and a lot more risk to take for now.

      • pfdietz 4 hours ago

        Once it's in orbit the cost of moving it farther out needed be very high. Just evaporating it with solar energy in very high orbit will allow the solar wind to carry it out of the solar system.

    • dpark 3 hours ago

      Unless you live in Sci Fi future where space travel is magically free, this is a pretty bad deal since sending a pound of spent nuclear fuel out of earth orbit takes 50+ pounds of fuel. Sending all the spent nuclear waste into space would be something like 10 million tons of fuel.

      • pfdietz 2 hours ago

        It doesn't have to be free, it just has to have a low cost. And remember, we're talking not about the cost now, but the cost up to centuries in the future. The ultimate time limit is set by when spent fuel stops being self-protecting against amateur diversion of the plutonium, which is 300-500 years.

        > 50+ pounds of fuel

        Just out of curiosity, how much do you think LOX/LNG propellant costs?

  • quirkot 5 hours ago

    Europe has about 60,000 tons of nuclear waste storage[1], so lets say the global nuclear waste quantity is 2-3x or 120,000 to 180,000 tons. That sounds like a lot, however it's less than 2 weeks of coal deliveries to a coal plant (at 1 train of 115 cars each with 116 tons of coal = 13,340 tons delivered per day[2]). To take another approach, the average landfill size is 600 acres[3].

    The "eh, just bury it" approach is really not a bad one. Its not even that much stuff to bury

    [1] https://worldnuclearwastereport.org/

    [2] https://www.eia.gov/todayinenergy/detail.php?id=16651

    [3] https://www.colorado.edu/ecenter/2021/04/15/hidden-damage-la...

    • fc417fc802 11 minutes ago

      I thought something like 30 tons per Gwatt capacity per year was the ballpark for high level waste without reprocessing? How are you arriving at a 120,000 ton estimate?

  • yabones 4 hours ago

    I don't see the issue with dry cask storage medium term, and deep geological storage long term. Spent fuel isn't really that dangerous once it's been cooled down and for a couple decades before putting it in the ground, to the point that there are far more dangerous natural things you can dig up.

    What concerns me is that 250 years of fossil fuel energy continues to store its waste products in my lungs and the water I drink. That's the issue we need to solve with urgency.

  • bigbadfeline 2 hours ago

    Fast neutron reactors can also "burn" waste from other reactors, the "ashes" are radioactive for only 300 years, there is no need for special storage after that. Untreated waste has to be kept in storage for around 100K years before it reaches safe levels of radioactivity.

    Other than marketing propaganda, there isn't much real information about Mark-0. I'm assuming it's a sodium cooled, slow and hot pebble bed reactor. Hot pebble beds are well known but one with sodium cooling appears to be a first.

    Why slow sodium? You get all the risks associated with sodium with none of the benefits of fast neutrons. There are operational, electricity producing, fast sodium reactors which do make some sense. I can't say the same for Mark-0.

Traubenfuchs 7 hours ago

I am still quite confused on the scientific consensus:

Should we double down on renewable energy and solve its issues with lots of batteries or should we invest in next generation nuclear energy?

Both at the same time?

Does anyone know?

  • datakan 7 hours ago

    Both at the same time. I don't see how putting all our eggs in a single basket benefits us.

  • bevekspldnw 6 hours ago

    When it comes to avoiding the worst impacts of the current catastrophic path we’re on, “nothing will work, but everything might”.

    Do it all.

    • pfdietz 6 hours ago

      Nuclear is not on a trajectory to do more than supply a minor amount of world energy. A (say) 10% nuclear, 90% renewable world is not an easier challenge than a 100% renewable world -- the intermittency/seasonality issues aren't eased by having 10% nuclear running as baseload, and keeping it as backup makes its cost per kWh explode.

      Nuclear really has to go big (supply most of the world's energy) or go home. But supplying most of the world's energy means burner reactors are inadequate -- there isn't enough cheap uranium. Burner microreactors have even worse neutron economy, so this argument applies even more so to them.

      • fssys 5 hours ago

        nuclear takes longer to come online though vs renewables can be very quick, so it makes sense to do both as a short-long term strategy

  • Tade0 6 hours ago

    China does: all of the above, where it makes sense.

    Renewables and batteries to keep your AC, workplace EV charger, stove, pool heater and (since recently) green ammonia producer going, nuclear to prevent e.g. aluminium smelters from seizing up.

    Also the cheapest way to make renewables work 24/7 is to build HVDC lines - they cost as much as a highway per unit length and even undersea cables would deploy for less and faster than equivalent nuclear.

    The total length of HVDC lines just in China is currently more than 40k km, so they've literally deployed enough of them to wrap around the globe.

    • api 5 hours ago

      China is also still building coal and has passed Europe and will (if they don’t change course) soon pass the US and Canada and the other big ones on a per capita emitter basis. They already passed everyone as top emitter in an absolute sense.

      https://ourworldindata.org/grapher/co-emissions-per-capita

      Not saying they’re not also building renewables and nuclear, but it seems like the policy is more “build anything and everything to satisfy demand” than a focused effort.

      BTW: if you look at US emissions, the data center bubble hasn’t had much if any effect. They are still trending down. There’s reasons to dislike that industry but I’m sick of the mindless echo chamber doom on that issue. They’re not that significant in the grand scheme of things.

  • sehansen 6 hours ago

    If your location already has a well-run nuclear energy sector (Finland, Sweden, South Korea): invest in nuclear energy.

    If you don't: stick to renewables.

    And it also depends on what you mean by "we". As a Dane, I don't think us Danish taxpayers should invest in nuclear energy, but I'm perfectly happy that private Danish investors invest in Seaborg/Saltfoss and Copenhagen Atomics.

  • pfdietz 6 hours ago

    Nuclear partisans like to call renewables ideological, but I think this is another example of "the accusation is a confession".

    The empirical evidence has nuclear being uncompetitively expensive. The current focus on variant reactor designs appears to be something of a Hail Mary attempt to get around this sad state of affairs.

    You sometimes see them making an argument about energy density, which goes back to Vaclav Smil. But Smil used this argument to massively mispredict how solar would be go in the market. We don't hear him much anymore.

    Nuclear advocates increasingly resort to conspiracy theoretic reasoning to explain away the failure of their technology to compete. This should be a red flag.

    • rayiner 5 hours ago

      > The empirical evidence has nuclear being uncompetitively expensive.

      France nuclearized 75% of its grid in the 1980s while the solar folks were faffing around. It's not a cost issue, it's that anti-nuclear folks have choked out the industry.

      We need to take the boot off the neck of nuclear. Wind and solar aren't an avenue to moving up the tech tree of civilization, which will involve using vastly more power.

      • pfdietz 5 hours ago

        We don't actually know how much that cost France, sine it was mixed in with their military nuclear effort. French auditors threw up their hands trying to figure out the actual costs.

        What we do know is their attempt to build more NPPs now has gone spectacularly tits up, with costs completely out of control. This should make one view their earlier efforts with great suspicion. Have they become much worse, or were earlier problems concealed?

        • rayiner 4 hours ago

          Costs are out of control due to nuclear regulation.

          • pfdietz 3 hours ago

            This is the conspiracy theory reasoning I was talking about. Nuclear is wonderful, but a global omnipotent green conspiracy has hobbled it.

            Or, maybe, it really is complicated and needs regulation to keep it sufficiently safe in a world where corners are always cut.

      • tech_ken 4 hours ago

        > moving up the tech tree of civilization

        Life isn't Civ 6, there is no tech tree to climb.

        • rayiner 4 hours ago

          Incorrect. Compare Bangladesh to the United States.

          • tech_ken 3 hours ago

            Tech development != tech tree, history is nonlinear and ecological. Linear, unlockable "tech trees" are an ahistorical fantasy necessary to make some video games fun and digestible. Applying them to the real world is like trying to win a war by replicating the Battle of Helm's Deep or something.

            • rayiner 3 hours ago

              I’m not saying it’s literally a tree. My point is that we need vastly more power to upgrade to the next level of civilization.

              • tech_ken 3 hours ago

                Right but “upgrading to the next level” is exactly the type of cognitive error that I’m against, it’s forward-looking Whig history. There is no “levels” of civilization, there’s only the arrangements we have now and the ones that will occur in the future. Maybe those arrangements will have different pros and cons than we have now, maybe they’ll have more sophisticated engineering practices, but there’s no objective “development score” that is being maximized it’s just more humanity.

                • fc417fc802 27 minutes ago

                  It's an abstraction, not an error. Naturally you might or might not agree with any individual's underlying metrics, and them with yours.

                  • tech_ken 12 minutes ago

                    > It's an abstraction, not an error.

                    Extending an abstraction beyond its expressive capabilities is an error IMO.

              • pfdietz 2 hours ago

                How do you know nuclear is even on the "tech tree", rather than being a blind alley? Isn't this argument just assuming what you're trying to show?

    • rs_rs_rs_rs_rs 5 hours ago

      >The empirical evidence has nuclear being uncompetitively expensive

      I have a solution, take the subsidies spent on "renewables" and put them into nuclear! Easy peasy!

      • bryanlarsen 4 hours ago

        Too late, governments have already subsidized nuclear more than they've subsidized renewables.

  • krunck 6 hours ago

    next generation nuclear energy = fusion

    • pfdietz 5 hours ago

      Fusion's main accomplishment will likely be to make fission look cheap in comparison, due to fundamental issues of power density in the nuclear island. Why make a huge complex low power density radioactive thing when you can make a much smaller simpler high power density radioactive thing?

  • rayiner 5 hours ago

    That's a political and economic question, not a scientific one. Science can provide input information, but the decision involves weighing all sorts of facts and considerations outside the scope of science.

    • mohamedkoubaa 5 hours ago

      Exactly. Waiting for a scientific consensus on a question that is very clearly not posed as a scientific question is oddly cultish

  • api 5 hours ago

    Both.

    We should be investing in all non carbon emitting sources and we should have been doing it since the 1970s when we figured out pretty conclusively that this would be a problem.

    Instead we had right wing fossil fuel shills on one shoulder and unscientific woo woo greens on the other, the net effect being that we kept burning more carbon. We still have them, Trump with “beautiful coal” and greens now opposing even solar power and batteries, but climate change is no longer possible to ignore. Some still manage it but those people are nuts.

    If we hadn’t stopped improving nuclear we’d probably have emitted half the CO2 we have. It would have become cheaper and safer and more scalable and then when China industrialized they would have copied that instead of burning so much coal.

    France with its nearly zero carbon grid is the existence proof.

    It wasn’t until the 2010s that solar and wind became grid scale in a big enough way to matter. That was too slow.

    Whether someone is at least open to nuclear power is my litmus test for whether they take climate change seriously.

    I do. If we hit 600, 800, 1000 ppm CO2, which is possible if the world keeps developing on the back of fossil fuels, we are entering existential risk territory. Earth has had those CO2 levels before, and higher, but our species was not alive then.

    We already passed the FAFO threshold for ppm CO2 and now we will FO. But that’s not X-risk yet. I’m talking about the next threshold, which may start around 600 but really kicks in near 1000. This is where you actually start asphyxiating. You get lowered IQ and impaired judgement to a small degree, but across the globe at a time when we really don’t need it.

  • tech_ken 4 hours ago

    It's more of an engineering call than something that can be purely determined from inductive reasoning. I think most engineers working in the space would say "both" are needed, but partisans exist on both sides.

sfn42 7 hours ago

> "The Trump administration is proud to support the rebirth of America’s nuclear industry and ensuring Americans have access to affordable, reliable and secure energy for generations to come."

> "The demonstration and the licensing pathway it establishes represent a key step toward deploying electricity-producing microreactors for U.S. military installations by September 30, 2028."

So which is it? Power to the people or power to the military? This microreactor concept doesn't seem very well suited for commercial use.

  • roenxi 7 hours ago

    Why would microreactor concepts not be suitable for commercial use? History is overwhelmed with examples of large, rare and expensive tech being produced in small cheap packages and becoming massive commercial successes that make the old way look primitive.

    • sfn42 6 hours ago

      Because large scale production is generally more scalable and efficient. And you probably don't want dozens of "microreactors" scattered across cities.

      • usrnm 6 hours ago

        > Because large scale production is generally more scalable and efficient

        Rooftop solar is an example of small scale decentralized energy production, maximum efficiency is not the only relevant metric.

        > And you probably don't want dozens of "microreactors" scattered across cities

        Why not? If they're considered safe and pass all inspections, what's the problem?

        • sfn42 6 hours ago

          A nuclear reactor is generally treated as a high security facility. I don't know how this new reactor works but I thought it was safe to assume something like a terrorist attack on one might be bad. It's also a lot more work to inspect and control them when scattered.

          Rooftop solar does not have these issues.

      • IsTom 6 hours ago

        On the other hand you can scale production of reactor themselves. And I don't think the idea is to scatter them around, but to have a power plant with dozens of them in one place (instead of 3-4 regular reactors in a regular nuke power plant).

      • seanhunter 6 hours ago

        I think that may be exactly wrong. The small scale may make it easier for a reactor to be “walk away safe” ie shut itself down absent external activity. I know that is a design goal of some of the Chinese micro reactors and those are used for civilian power generation.

        Secondly although generating large amounts of power is more efficient in terms of generation, generating power close to the point of use is significantly more efficient in terms of power loss on the grid as I understand it.

      • roenxi 6 hours ago

        Large scale production of commodity goods is generally more efficient. Which is why microreactors don't seem to have any inherent disadvantages. The efficiencies tend to kick in with the raw number of items produced.

        • pfdietz 6 hours ago

          > microreactors don't seem to have any inherent disadvantages

          They have diseconomies of scale. Some of the costs of a nuclear power plant scale sublinearly with power. Neutron economy is improved in a larger core. Larger turbines are more efficient than smaller turbines. It doesn't take 1000x as many operators to operate a NPP with 1000x the power output.

          • roenxi 5 hours ago

            Is that relevant? The economics of nuclear plants doesn't have anything to do with efficiency as far as I'm aware, the fuel costs are relatively negligible. They can afford to be horribly inefficient if they can get economies of scale producing the plant. So you can use inefficient turbines and have bad neutron economy and it wouldn't change the economics by anything in particular.

            You'd also probably find similar issues with diesel generators, but small diesel generators do roaring trade and have great commercial applications.

            • pfdietz 5 hours ago

              Cost is not only relevant, it's paramount. Efficiency is only important insofar as it affects overall cost.

              Diesel generators have the advantage of being very cheap -- an order of magnitude cheaper than NPPs per unit power output -- and of having much of their total cost being fuel cost, so they can operate at lower capacity factor. But even so, we don't see large power plants composed of arrays of diesel microgenerators.

              (The solution for current higher capacity factor diesel users, like say remote operation at mines, would be to supplement them with renewables and storage to reduce fuel costs. This is already happening.)

              A significant problem with any small power plant is fixed costs. A 1 MW(e) plant (Antares is said to be between 100 kW(e) and 1 MW(e)) making power at 90% capacity factor and selling at $0.05/kWh will gross about $400K/year. A single full time employee, like a security guard, will cost a good chunk of that.

              • roenxi 5 hours ago

                > Cost is not only relevant, it's paramount. Efficiency is only important insofar as it affects overall cost.

                Oh sorry, I thought you were talking about efficiency. Ok, what is the cost is for these plants?

                > A single full time employee, like a security guard, will cost a good chunk of that.

                I dunno, a 1MW nuclear plant could end up being pretty small. It might easily be economic to install them places that already have security guards.

                • pfdietz 5 hours ago

                  Microreactors have been tried before by the military, for use at bases, which have guards. They not only didn't make sense to install, they didn't make sense to continue to operate once installed.

    • pfdietz 6 hours ago

      > Why would microreactor concepts not be suitable for commercial use?

      Crippling diseconomies of scale.

  • ablation 7 hours ago

    "Antares is a nuclear fission energy company developing compact microreactors for defense and space applications"